通过热重和差示扫描量热(TG-DSC)同步热分析仪，分别在空气气氛及富氧条件下，研究3种焦样燃烧过程的质量变化和热效应。得出空气气氛下，随着加热速率的增加，释热速率曲线的峰值增加，最大释热速率对应的温度则出现滞后，最大释热加速度对应的温度 max(Ta )增加，加速度峰值(amax)也随之增加； maxaT 越低，amax越高，表明煤焦活性越高。富氧条件下，随着氧气体积分数从21%,增加至100%,，最大释热速率逐渐增大，释热速率曲线呈现出越来越高及窄的趋势， maxaT 呈现出下降的趋势，amax呈上升趋势；相同氧体积分数下(21%)，空气气氛 amax值大于富氧条件下的值，说明焦样在空气条件下的反应活性较高，随着煤阶的增加， maxaT 增大，amax递减，表明煤焦反应活性逐渐降低。%The combustion characteristics of three different char samples were investigated by using differential scanning calorimeter(DSC)and thermogravimetry analysis(TG) in order to research the mass change and heat effect of char combustion.Under the air atmosphere,the peak value of DSC curve increases with heating rates increasing, while the temperature corresponding to the maximum rate of heat release shows a delay time,the temperature corre-sponding to the maximum acceleration of heat releasemax(Ta)and the peak value of acceleration(amax)increase as heat-ing rates increase.AsmaxaTdecreases andamaxincreases,the reactivity of coal char increases.Under the oxy-fuel combustion,as the oxygen volume concentration increases from 21%, to 100%,,the maximum rate of heat release increases,DSC curve gets higher and narrower,maxaT tends to decline,whileamax tends to increase.Underthe same oxygen volume concentration(21%),the value ofamax in air is greater than that in oxy-fuel,which showsthat the reactivity of char in air is higher than that in oxy-fuel combustion,and with the increase of coal rank,maxaTin-creases andamax declines,indicating a decrease in the reactivity of coal char.
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